Automatic battery detection system and method for detecting a rechargeable battery with low remaining charge

ABSTRACT

A system includes a charging cradle that receives a electronic hand-held device powered by a battery. Inside the charging cradle a controller performs a method of internal-device battery cell detection, i.e., distinguishing between NiMH/NiCd and other types of cells in the battery, before recharging the battery. A method determines the cell chemistry without any modifications to the battery and/or without any user input by performing tests on the battery. The tests include a Battery Voltage Test, an Internal Resistance Test, and a Timed Voltage Test. The testing is performed through a combination of hardware and software in the charging cradle. By performing the tests in a preferred order, detected alkaline, lithium, rechargeable alkaline, and carbon-zinc cells, damaged NiMH and NiCd cells, and close to fully charged NiMH and NiCd cells cause termination of a recharging operation before damage to the device or battery is sustained.

BACKGROUND OF THE INVENTION

The present invention relates to a system and method for testing abattery to determine if it is a rechargeable battery. More specifically,the present invention relates to an automatic battery detection systemand method for use with a wireless telecommunications device having awireless transceiver powered by a battery. The wirelesstelecommunications device is placed in an associated charging cradle totest the battery. This testing is performed by a controller in thecharging cradle that determines if the battery includes a rechargeablecell and, if it does, if the rechargeable cell needs to be recharged.

Generally, wireless transceivers, such as those used in radios, cellphones, pagers, etc., are powered by rechargeable batteries. Mostcommercially available rechargeable cells, such as Nickel Metal Hydride(NiMH) or Nickel-Cadmium (NiCd) cells, are recharged by an externalcharger (i.e., the user removes the batteries from the device andrecharges them in the external charger). However, some devices rechargethe batteries without removing them from the device.

To recharge the battery without removing it from the device, the type ofcell within the battery must first be determined by the device. Usually,the rechargeable batteries are modified to facilitate cell-typedetection. This modification of the battery typically is done by addinga third terminal to the battery where detection is performed by adetector that measures the batteries characteristics through anelectrical contact with the third terminal.

Another method of in-unit cell detection is performed through some formof user input such as a mechanical switch with an arrow that is lined upwith one or more markings on the device. These markings representchemical symbols or words that indicate the cell-type of the battery tothe device charging the cell.

When recharging a battery though a charging cradle it is necessary tofirst test the battery to reduce the possibility of damaging either thedevice or the battery. If a device having a non-rechargeable battery isplaced in the charging cradle during a recharging operation both thebattery and the device could be damaged. Further, if a rechargeablebattery is recharged when it is already almost fully charged, the numberof charging cycles is lowered and the lifetime of the battery isdrastically reduced.

SUMMARY OF THE INVENTION

According to the present invention, a charging cradle receives atelecommunications device powered by a battery. Inside the chargingcradle a controller performs a method of internal-device battery celldetection, i.e., distinguishing between NiMH/NiCd and other types ofcells in the battery, before recharging the battery. A method determinesthe cell chemistry without any modifications to the battery and/orwithout any user input by performing a plurality of tests. The tests mayinclude a Battery Voltage Test, an Internal Resistance (IR) Test, and aTimed Voltage Test. The plurality of tests are preferably executed in apredetermined order. The testing is performed through a combination ofhardware and software in the charging cradle.

One advantage of the present invention is that alkaline, lithium,rechargeable alkaline, and carbon-zinc cells are detected and notrecharged while the battery remains in the device without modifying thebattery, which protects the device from being damaged.

Another advantage of the present invention is that damaged NiMH and NiCdcells are detected and not recharged while the battery remains in thedevice without modifying the battery, which protects the device frombeing damaged.

Still another advantage of the present invention is that close to fullycharged NiMH and NiCd cells are detected and not recharged while thebattery remains in the device without modifying the battery, whichextends the life of the battery and prevents overcharging of thebattery.

These are just a few of the many advantages of the invention, which isdescribed in more detail below in terms of a preferred embodiment. Aswill be appreciated, the invention is capable of other and differentembodiments, and its several details are capable of modifications invarious respects, all without departing from the invention. Accordingly,the drawings and description of the preferred embodiments are to beregarded as illustrative in nature and not restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be apparent to those skilled in the art uponreading the following description in view of the accompanying drawings,wherein:

FIG. 1 is a high-level block diagram of a system according to apreferred embodiment of the present invention;

FIG. 2 is a detailed circuit architecture of the system of FIG. 1according to a preferred embodiment of the present invention;

FIG. 3 is a detailed circuit architecture of a section of the system ofFIG. 1 according to a preferred embodiment of the present invention;

FIG. 4 is a flow chart of the overall battery detection method accordingto a preferred embodiment of the present invention;

FIG. 5 is a flow chart of a Battery Voltage Test according to apreferred embodiment of the present invention;

FIG. 6 is a flow chart of an IR Test according to the preferredembodiment of the present invention; and

FIG. 7 is a flow chart of a Timed Charge Test according to a preferredembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

An apparatus 10 comprising a preferred embodiment of the presentinvention is shown in FIG. 1. The apparatus 10 includes an externalpower source adapter 12, preferably an AC adapter, a holder 14 (orcharging cradle), and a telecommunications device 16 (or an electronichand-held device). The device 16 is preferably an Inter@ctive (PM) Pager850, which is manufactured by Research In Motion Limited (RIM), and theholder 14 is preferably an Inter@ctive (PM) Pager 850 Charging Cradle,which is also manufactured by RIM for use with the pager 16. It is to beappreciated that although these are the preferred devices other devicesfor use with the present invention that operate in a similar mannercould also be used.

With continuing reference to FIG. 1, the holder 14 preferably includes aDC—DC converter 18, a switch block 20, a constant current source 22, acontroller 24, and an external user interface 26. The converter 18 ispreferably a 12V to 5V converter, which converts voltage received fromthe adapter 12 and sends the converted voltage to the switch block 20.Electricity flowing through the switch block 20 to the constant currentsource 22 is controlled by the controller 24.

The device 16 preferably includes a battery 28, a Schottky diode 30, adevice circuit 32, and a temperature detection circuit 34. Through useof the Schottky diode 30, the constant current source 22 in the holder14 is protected from reverse current since the diode 30 only permitscurrent flow into the telecommunications device 16. The controller 24performs tests on the battery 28 by reading the voltage at node 36 ofthe device 16 to determine if the battery 28 contains rechargeable NiMHor NiCd cells that need to be recharged. The battery 28 is recharged bythe constant current source 22 when the controller 24 determines thatthe battery 28 is a rechargeable battery that is in need of recharging.Also, the controller 24 monitors other parameters of thetelecommunications device 16, such as temperature, through a temperaturedetection circuit 34.

The device circuit 32 is preferably configured to operate as a wirelesstransceiver, such as a two way paging computer, a portable electronicmessaging device, or a hand held e-mail client. An example of such adevice is set forth in co-pending U.S. patent application Ser. No.09/106,585 titled “Hand-Held Electronic Device With a Keyboard Optimizedfor Use With The Thumbs”. This application is hereby incorporated intothis disclosure by reference. Although this is the preferred devicecircuit 32, other types of circuits could be utilized in the presentinvention.

The external interface 26 of the holder 14 is preferably either alight-emitting diode (LED) or a graphical user interface (GUI) thatalerts a user of the device 16 the status of the testing beingperformed. For example, an LED illuminates continuously during thedetecting. Then, if the controller 24 determines the battery 28 containsNiCd or NiMH cells that need to be recharged, the LED blinks until arecharging cycle is completed at which time the LED is illuminatedcontinuously again. In the alternative embodiment with the GUI, theexternal interface 26 made be located on the holder 14 or a be acomputer monitor (not shown) that is coupled to the holder 14. Further,the information can alternatively be displayed on a GUI 38 of the pager16.

Turning to FIG. 2, a preferred circuit architecture of the components inthe holder 14 are shown in more detail. The switching block 20 controlsthe flow of current from the converter 18 to the constant current source22 by only allowing current to pass through it when it is turned ON bythe controller 24. This occurs when the controller 24 determines thebattery 28 needs to be recharged. Further, when current flows throughswitch block 20 it acts as an amplifier. The switch block 20 includes alow pass filter 50, a NP load switch circuit 52, and a filteringcapacitor 54. The low pass filter 50, which includes resistor 56 andcapacitor 58, filters the power from the converter 18. Preferably, thelow pass filter 50 includes a 100 k Ω resistor 56 and a 1000 pFcapacitor 58, and the value of the filtering capacitor 54 is 1 uFcapacitor.

As seen in FIG. 3, a preferable circuit for the NP load switch circuit52 is shown, which is a FCD6363L connection circuit FairchildSemiconductor INS. manufactured by . This connection circuit 52 includesa p-channel, high current MOSFET 60 with a diode 62 connected drain tosource across the FET 60 and an n-channel, low current MOSFET 64 with adiode 66 connected source to drain across the FET 64. By connecting thelow pass filter 50 to the MOSFET 60 in this configuration, the MOSFET 60acts as an amplifier so that any signal passing through MOSFET 60, whenit is conducting, is amplified. Further, the MOSFET 64 is configured asa switch that is switched to an ON state by the controller 24 by biasingthe gate of the MOSFET 64. Then, based on the ON state of MOSFET 64, thegate of MOSFET 60 is biased, switching it to an ON state. In the ONstate, the MOSFET 60 allows electricity to flow through the switch block20 to the constant current source 22 via the filtering capacitor 54.

With continuing reference to FIGS. 2-3, the constant current source 22includes a constant voltage circuit 70 and a low pass filter 72. Acapacitor 74 and a resistor 76 make up the low pass filter 72. Theconstant current source 22 further includes two resistors 78 and 80across which there is a constant voltage from the constant voltagecircuit 70 such that the constant voltage is converted into the constantcurrent. This constant current flows into the telecommunications device16 via a filtering capacitor 82. Further, the constant current source 22only conducts when MOSFETS 60 and 64 are turned on by the controller 24during a recharging operation of battery 28. Preferably, the constantvoltage circuit 70 is a EZ1117CM circuit manufactured by SemtechCorporation Microage Technology. Also, preferably the value of capacitor74 is 0.1 uF, the value of resistor 76 is 383 Ω, the value of resistors78 and 80 are 1 Ω each, and the value of capacitor 82 is 10 uF.

As also seen in FIGS. 2-3, the controller 24 includes a control circuit84 and a low pass filter 86. The low pass filter 86, which includes aresistor 88 and a capacitor 90. Preferably, the control circuit 84 is aPIC16C711 control chip manufactured by Microchip Technology, Inc., thevalue of resistor 88 is 10 k Ω, and the value of capacitor 90 is 6800pF.

In this configuration, through the method 100 described in detail below,the controller 24 determines what type of cells are contained in thebattery 28 without any previous knowledge of the cell-type. Thedetermination is made when the device 16 is properly inserted into theholder 14. Once proper insertion is detected, the controller 24 startstesting of the battery 28. If the testing is successful, i.e., thebattery 28 is rechargeable and in need of recharging, the controller 24turns ON the FET 64 by biasing its gate. Then, once the FET 64 is turnedON, the amplifying FET 60 is turned ON, which permits current flow fromthe converter 18 to the constant current source 22. The current thenpasses through the constant current source 22 into the device 16 torecharge the battery 28.

FIG. 4 sets forth a preferred method 100 of cell detection performed bythe controller 24, which allows for differentiation between NiMH/NiCdcells and other cells. By applying this method of testing, thecontroller 24 detects and does not recharge an alkaline, lithium,rechargeable alkaline, and carbon-zinc cells, damaged NiMH and NiCdcells, and close to fully charged NiMH and NiCd cells.

With continuing reference to FIG. 4, once it has been determined thatthe device 16 is properly positioned in the holder 14, the testing isstarted at step 102. A plurality of tests are preferably performed bythe controller 24 to determine the presence of a “good” NiMH or NiCdcell in the battery 28. Three of the plurality of tests include aBattery Voltage Test 104, an Internal Resistance (IR) Test 106, and aTimed Charge Test 108. As shown in step 110, for a successful detectionof a NiMH or NiCd cell, these tests 104-108 should be passed in apredetermined order, although alternatively they could be configured tooperate in a different order. If any of the three tests 104-108 fail,then at step 112 a user is alerted, via the external interface 26, thatthe recharging operation is being terminated. These tests 104-108 aredescribed in more detail below with reference to FIGS. 5-7.

FIG. 5 sets forth the preferred Battery Voltage Test method 104. TheBattery Voltage Test 104 is started at step 200. At step 202 thecontroller 24 reads the voltage V_(BAT) of the battery 28 at node 36through the coupling element 92. Then, at step 204, the controller 24determines if the voltage V_(BAT) is below a certain threshold value,preferably 1.396 V. If the voltage V_(BAT) is below the threshold value,then the Battery Voltage Test 104 test was successful and the method 100proceeds to the IR Test 106 at step 206. If the voltage V_(BAT) is equalto or above the threshold value, then the user is alerted, via theexternal interface 26, that the recharging operation is being terminatedto ensure there is no damage to the battery 28 or the device 16.

In the preferred embodiment of the present invention, the controller 84reads the battery voltage 16 times. The purpose of sampling the voltage16 times is to remove any random (or white) noise that could be seen onthe coupling element 92. The 16 samples are then averaged as V_(BAT) andcompared to the threshold voltage of 1.396 V. The reason for performingthe Battery Voltage Test 104 is because most fully charged alkaline andlithium AA cells have voltages above the specified threshold. Further,most fully charged NiMH and NiCd cells have a terminal voltage in theneighbourhood of the threshold voltage. Therefore, the Battery VoltageTest 104 detects both fully charged NiMH and NiCd cells (to preventovercharging) and non-rechargeable cells.

FIG. 6 sets forth the preferred steps of the IR Test 106. The IR Test106 determines the internal resistance of the battery 28 inside thedevice 16 to determine the cell-type. The NiMH and NiCd cells have a lowinternal resistance (due to their construction) such that their lowerIRs allow them to be differentiated by this test. The IR values, V_(AA1)and V_(AA2), are measured by determining the pulse height voltageresponse to a 20 ms current pulse.

The IR Test 106 is performed by the controller 24 as follows. Once theBattery Voltage Test 104 has passed, at step 302 the IR Test 106 isstarted. A first voltage V_(AA1) of the battery 28 is read and stored atstep 304. Then, at step 306 the first voltage V_(AA1) is compared to apredetermined voltage value, preferably 1.1 V. Based on this comparison,at step 308 a threshold voltage value V_(T) is determined and set sothat it is used during testing. Preferably, the threshold voltage V_(T)is set at 137 mV if V_(AA1) is equal to or greater than 1.1 v or V_(T)is set at 200 mV if V_(AA1) is less than 1.1 V. Then, a sample-countvalue and a pass-count value are both set to 0 at step 310. At step 312,the controller 24 enables test charging of the battery 28, preferably ata rate of 630 mA for 20 ms. During the test charging, a second batterycell voltage V_(AA2) is read and stored at step 314. This second cellvoltage V_(AA2) is then subtracted from the first cell voltage V_(AA1)to determined a difference value that is then compared to the thresholdvoltage V_(T) at step 316. If the difference V_(AA1)−V_(AA2) is lessthan the threshold voltage V_(T), then (1) the pass-count value isincremented to pass-count +1 at step 318, (2) the testing is delayed apredetermined time period at step 320, which is preferably 1 ms, and (3)the sample-count value is incremented to sample-count +1 at step 322.Otherwise, if the difference V_(AA1)−V_(AA2) is equal to or above thethreshold voltage V_(T), then only steps 320 and 322 are performed andthe pass-count value step 318 is by-passed.

At step 324, the controller 24 determines whether or not 20 voltagesamples V_(AA2) have been read, stored, and used to calculate thedifference value for the comparison to the threshold value. If it isdetermined that there have been less than 20 samples, steps 314-324 arerepeated until the sample-count is equal to 20. Otherwise, if it isdetermined that 20 samples have been taken, then the test charging isdisabled at step 326. After disabling the test charging at step 326, adetermination is made at step 328 if the pass-count value is greaterthen or equal to 14, i.e., at least 14 times during the 20 samples thevoltage difference V_(AA1)−V_(AA2) was less than the threshold voltageV_(T) at step 316. If the pass-count value is equal to or above 14, thenthe method 100 proceeds to the Timed Charge Test 108 at step 330.Otherwise, if the pass-count value is less than 14, then the user isalerted at step 332, via the external interface 26, that the rechargingoperation is being terminated.

The threshold voltage V_(T) of 137 mV was chosen because most healthyNiMH and NiCd AA cells have a jump in their terminal voltage, during the20 ms charge, of less than 137 mV. The NiMH and NiCd cells that do notfall below this value are usually damaged cells. Also, the thresholdvoltage V_(T) of 200 mV was chosen because as cell voltage decreases IRrises so this must be taken into account. Further, the predeterminedpass-count value of 14 was used because a non-insignificant noise flooris seen at the input pin to an A/D converter (not shown) in the controlcircuit 84. Therefore, having 14 sample results (of the subtraction) isrequired to accurately track the shape of the pulse created by chargingfor 20 ms.

FIG. 7 sets forth the preferred steps of the Timed Charge Test 108. Themethod 100 proceeds to the Timed Charge Test 108 at step 402 once thebattery 28 has passed the Battery Voltage Test 104 and the IR Test 106.At step 404, a sample-count value is set to 0. Then, test charging ofthe battery 28 is enabled at step 406. The controller 24 enablescharging (at a rate of 630 mA) into the cells within the battery 28 fora period of five seconds. During this period of time, the controller 24measures the voltage of battery 28 at node 30 in 17 equally time-spacedsets of 16 samples per set, which are then averaged as V_(BAT) at step408. At step 410, it is determined if V_(BAT) is above a predeterminedthreshold value, preferably 1.553 V. If V_(BAT) is above this thresholdvalue, then the test charging is disabled at step 412. If this occurs,the user is alerted at step 414, via the external user interface 26,that the recharging operation is being terminated. Otherwise, if theV_(BAT) is below the threshold value, the Timed Charge Test 108 isdelayed a predetermined time period, preferably 0.3 seconds, at step416, and then the sample-count value is increased by 1 to sample-count+1 at step 418.

Following the delay at step 416 and increment at step 418, thesample-count value is compared to a predetermined sample-count value atstep 420, where the predetermined sample-count value is preferably 17.If the sample-count value is less than 17, then steps 408-418 arerepeated until the sample-count is equal to 17. Otherwise, the testcharging is disabled at step 422, and at step 424 the cell inside thebattery 28 is considered to be a NiMH or NiCd cell in need ofrecharging. If this is determined at step 424, the controller 24 willbias the gate of the MOSFET 64 so that it is in an ON state allowingelectricity to flow through MOSFET 64 and the constant current source 22to the device 16 to begin recharging the battery 28.

The value of 1.553 V as the threshold level for the VBAT comparison isused because most NiCd and NiMH AA cells, when charged for five secondsat a rate of 630 mA, have terminal voltages that rise to less than 1.553V. However, NiMH and NiCd cells that are not ready to be recharged haveterminal voltages that are above 1.553 V. Thus this test 108, accordingto a preferred embodiment of the present invention, detects and does notrecharge NiMH or NiCd cells that are close to fully charged. The TimedCharge Test 108 detects and does not recharge any non-NiMH and non-NiCdAA cells 28 that may have passed the previous two tests 104 and 106.These three tests 104-108 in the preferred combination accurately detectthe presence of either a non-NiCd/NiMH cell or a near fully chargedNiCd/NiMH cell when the telecommunications device 16 is positioned inthe holder 14. Finally, although some non-preferred cells may pass anyof the three tests 104-108 individually, it is doubtful that the cellswould not be detected and pass all three of the battery detection tests104-108 in the combination as taught in the preferred embodiment of thepresent invention.

The invention has been described with reference to preferredembodiments. Those skilled in the art will perceive improvements,changes, and modifications. Such improvements, changes and modificationsare intended to be covered by the appended claims.

We claim:
 1. An apparatus, comprising: a power source; an electronichand-held device powered by the power source; and a holder including acontroller that is operative to determine, prior to beginning arecharging operation, if the power source should not be recharged whenthe electronic hand-held device is in the holder.
 2. An apparatusaccording to claim 1 wherein the power source is a battery.
 3. Anapparatus according to claim 1 wherein the electronic hand-held deviceis a wireless transceiver.
 4. An apparatus according to claim 3 whereinthe wireless transceiver is a two-way paging computer.
 5. An apparatusaccording to claim 3 wherein the wireless transceiver is a portableelectronic messaging device.
 6. An apparatus according to claim 1wherein the controller is configured to measure predeterminedcharacteristics of the power source.
 7. An apparatus according to claim1 wherein the controller is configured to perform a battery voltagetest.
 8. An apparatus according to claim 7 wherein when performing thebattery voltage test the controller is operative to determine if a powersource voltage value is below a threshold value.
 9. An apparatusaccording to claim 1 wherein the controller is configured to perform aninternal resistance (IR) test.
 10. An apparatus according to claim 9wherein when performing the IR test the controller is operative todetermine if a difference between a first power source voltage value anda second power source voltage value is below a predetermined thresholdvalue a predetermined number of times.
 11. An apparatus according toclaim 1 wherein the controller is configured to perform a timed chargetest.
 12. An apparatus according to claim 11 wherein when performing thetimed charge test the controller is operative to determine if a powersource voltage value is below a predetermined threshold value.
 13. Anapparatus according to claim 1 wherein the controller is configured toperform a battery voltage test and an IR test.
 14. An apparatusaccording to claim 13 wherein: when performing the battery voltage testthe controller is operative to determine if a first power source voltagevalue is below a first threshold value; and when performing the IR testthe controller is operative to determine if a difference between asecond power source voltage value and a third power source voltage valueis below a second predetermined threshold value a predetermined numberof times.
 15. An apparatus according to claim 1 wherein the controlleris configured to perform a battery voltage test and a timed charge test.16. An apparatus according to claim 15 wherein: when performing thebattery voltage test the controller is operative to determine if a firstpower source voltage value is below a first threshold value; and whenpreforming the timed charge test the controller is operative todetermine if a second power source voltage value is below a secondpredetermined threshold value.
 17. An apparatus according to claim 1wherein the controller is configured to perform an IR test and a timedcharge test.
 18. An apparatus according to claim 17 wherein: whenperforming the IR test the controller is operative to determine if adifference between a first power source voltage value and a second powersource voltage value is below a first predetermined threshold value apredetermined number of times; and when preforming the timed charge testthe controller is operative to determine if a third power source voltagevalue is below a second predetermined threshold value.
 19. An apparatusaccording to claim 1 wherein the controller is configured to perform abattery voltage test, an IR test, and a timed charge test.
 20. Anapparatus according to claim 19 wherein: when performing the batteryvoltage test the controller is operative to determine if a first powersource voltage value is below a first threshold value; when performingthe IR test the controller is operative to determine if a differencebetween a second power source voltage value and a third power sourcevoltage value is below a second predetermined threshold value apredetermined number of times; and when preforming the timed charge testthe controller is operative to determine if a fourth power sourcevoltage value is below a third predetermined threshold value.
 21. Anapparatus according to claim 1 wherein the controller is configured tosequentially perform a battery voltage test, an IR test, and a timedcharge test.
 22. An apparatus according to claim 21 wherein whenperforming the battery voltage test the controller is operative todetermine if a first power source voltage value is below a firstthreshold value; when performing the IR test the controller is operativeto determine if a difference between a second power source voltage valueand a third power source voltage value is below a second predeterminedthreshold value a predetermined number of times; and when preforming thetimed charge test the controller is operative to determine if a fourthpower source voltage value is below a third predetermined thresholdvalue.
 23. An apparatus according to claim 1 further comprising: anexternal user interface coupled to the controller which is configured toprovide a user information regarding a status of testing performed onthe battery.
 24. An apparatus according to claim 23 wherein the externaluser interface comprises a light-emitting diode.
 25. An apparatusaccording to claim 23 wherein the external user interface comprises agraphical user interface.
 26. The apparatus according to claim 1,wherein the controller determines if the power source is anon-rechargeable power source, a damaged or abnormal rechargeable powersource, or a nearly filly charged rechargeable power source to therebydetermine whether the power source should not be recharged.
 27. Theapparatus according to claim 1, wherein the power source is replaceableby a user of the electronic hand-held device.
 28. A method, comprisingthe steps of: powering an electronic hand-held device with a powersource; testing the power source when the electronic hand-held device isheld by a holding device, the testing being performed by a controller inthe holding device, prior to beginning a recharging operation, todetermine if the power source should not be recharged; and controllingan operation of the electronic hand-held device based on the testingstep.
 29. A method according to claim 28 wherein the testing stepcomprises performing a timed charge test.
 30. A method according toclaim 28 wherein the testing step comprises: performing a power sourcevoltage test; and performing an IR test.
 31. A method according to claim28 wherein the testing step comprises: performing a power source voltagetest; and performing a timed charge test.
 32. A method according toclaim 28 wherein the testing step comprises: performing an IR test; andperforming a timed charge test.
 33. A method according to claim 28wherein the testing step comprises: performing a power source voltagetest; performing an IR test; and performing a timed charge test.
 34. Amethod according to claim 33 wherein the IR test is only performed ifthe power source voltage test passes, and the timed charge test is onlyperformed if the IR test passes and all three tests must pass for arecharging operation to begin for the power source.
 35. A methodaccording to claim 28 wherein the testing step comprises performing apower source voltage test.
 36. A method according to claim 28 whereinthe testing step comprises performing an IR test.
 37. The methodaccording to claim 28, wherein the controller determines if the powersource is a non-rechargeable power source, a damaged or abnormalrechargeable power source, or a nearly fully charged rechargeable powersource to thereby determine that the power source should not berecharged.
 38. The method according to claim 28, wherein the powersource is replaceable by a user of the handheld electronic device. 39.An apparatus for testing a battery, the apparatus comprising: a handheldelectronic device powered by the battery; and a charging cradle thatcomprises a controller that is operative to perform tests on the batterywhen the handheld electronic device is held by the charging cradle, thetests being operative to determine, prior to beginning a rechargingoperation, if the battery should not be recharged.
 40. An apparatusaccording to claim 39 wherein the transceiver device is a two-way pagingcomputer.
 41. An apparatus according to claim 39 wherein the transceiverdevice is a portable electronic messaging device.
 42. An apparatusaccording to claim 39 wherein the transceiver device is a hand-helde-mail client.
 43. The apparatus according to claim 39, wherein thecontroller determines if the battery is a non-rechargeable battery, adamaged or abnormal rechargeable battery or a nearly fully chargedrechargeable battery to thereby determine that the battery should not berecharged.
 44. The apparatus according to claim 39, wherein the batteryis replaceable by a user of the handheld electronic device.
 45. A methodfor determining if a battery powering a handheld electronic devicetransceiver should not be recharged, the method comprising the steps of:performing a battery voltage test on the battery; performing an IR teston the battery; and performing a time charge test on the battery; thetesting of the battery being performed by a controller in a chargingcradle when the transceiver is held in the charging cradle, prior tobeginning a recharging operation.
 46. A method according to claim 45wherein the IR test is only performed if the power source voltage testpasses, and the timed charge test is only performed if the IR testpasses and all the tests must pass for a recharging operation to beginfor the battery.
 47. The method according to claim 45, wherein thecontroller determines if the battery is a non-rechargeable battery, adamaged or abnormal rechargeable battery or a nearly fully chargedrechargeable battery to thereby determine that the battery should not berecharged.
 48. The method according to claim 45, wherein the battery isreplaceable by a user of the handheld electronic device.
 49. A system,comprising: means for receiving electricity from a first power sourceand for converting the electricity such that it flows into and throughthe system; means for controlling the system, the means for controllingthe system controlling a plurality of tests performed on a second powersource that powers a device, the tests determining, prior to beginning arecharging operation, if the second power source should not berecharged, and, responsive to the tests, controlling a switch used toturn on an amplifier that amplifies the electricity flowing through thesystem; means for outputting constant current when the switch is turnedon such that the constant current flows into the second power source torecharge the second power source while it is located in the device; andmeans for indicating a status of the system to a user.
 50. A systemaccording to claim 49 wherein the controlling of the plurality of testsincludes controlling a battery voltage test, an IR test, and a timedcharge test performed in a predetermined order for determining a type ofcell contained in the second power source and a charge on the cell. 51.The system according to claim 49, wherein the tests determine if thesecond power source is a non-rechargeable power source, a damaged orabnormal rechargeable power source, or a nearly fully chargedrechargeable power source to thereby determine that the second powersource should not be recharged.
 52. The apparatus according to claim 49,wherein the second power source is replaceable by a user of theelectronic handheld device.